Centrifugal governor and speed-indicator.



P, 0. DORER. OBNTRIFUGAL GOVERNOR AND SPEED INDICATOR.

APPEIGATION FILED SEPT. 7, 1912.

1,073,031. Patented Sept. 9, 1913.

UNITED}srArEs PATENT oEEroE.

rnnvrus o'r'ro DORER, or LEE, E GLAND, ASSIGNOR. 'ro s. SMITH & son, LIMITED, or

WESTMINSTER, ENGLAND.

V CENTRIEUGAL GovEaNoa AND srE n-InnIcA'roR.

To all whom, it may concern Speed-Indicators, of which the following is a specification;

This invention relates to centrifugal governors, speed indicators and the like, the object being to provide mechanism which shall be superior to those hitherto employed as regards uniformity and accuracy of action. I

Hitherto, in some centrifugally-operated mechanisms a weighted governor arm has been connected with a sleeve, or with some other movable member, by means of a link, with the result that, as the governor arm moved outward under the centrifugal action, the angularity of the link with reference to the arm, or to the movable member, or with reference to both, varied in such a way that the amount of movement imparted to the said member for a given change of speed of the revolving element at low speeds was greater than that imparted forthe same change of speed ofthe revolving element at higher speeds. In other constructions cams have been employed to correlate in arious desired manners, the movements.

of the governor arms themselves. Such cams have commonly been employed in pairs symmetrically spaced 1n order to produce symmetry in the resulting forces, but where the space available is small, the employment of cams in duplicate cannot be followed. I have further discovered that yet another cause of irregularity, where the forces acting'upon the movable member are not symmetrically applied or are unbalanced for any reason, arisen from the production, in these circumstances, of a forcetending to bind the said movable member frictionally upon its guide or mounting." Irregularity was further introduced by the fact that if the governor arm when in its position of rest is approximately parallel to the governor spindle, it is'movedoutward very considerably without being appreciably lifted, while the converse holds good at the other limit of its possible movement.

"According to this invention, there is employedin a speed indicator or like centrif- Specification of Letters Patent. Applioatio n filed September 7, 1912.

Patented Sept. 9, 1913. Serial No. 719,220.

ugal mechanism, in conjunction with a governor arm or other centrifugal mass, a single hook-like cam rigidly supported upon a form of a hook-like member, as just here inbefore referred to, the member carrying itis liable to be subjected to a force tending to bind it frictionally upon its guide or mounting, and this frictional binding is inimical to responsiveness of action. This I have found to be the case notably in connection with speed indicators such as are employed on self propelled vehicles. The said binding effect prevents a change in position of the member subjected to it until the change in speed has become sufliciently great to allow the operating force to more than overcome the binding effect. In order to deal with this, I introduce a force to counteract the said binding effect, for example, by suitably inclining the cam-face to the direction of movement of the said member, so that the cam serves to apply both such a counteracting force and an operating force.

In the accompanying drawings :-F igure 1 is an elevation in part section of a centrifugal governor device according to this invention as applied to a speed indicator, and Fig. 2 is an elevation at right angles to Fig. 1.

Like letters indicate like parts in both the figures.

Upon the spindle .A is carried a ring B which constitutes the centrifugally-operated element. A support for the ring is provided by two pivots disposed across the diameter of the ring, the pivots being shown at C and being carried by a cap or bell-like sleeve C rigidly connected to the spindle A. A sleeve D is mounted upon the spindle and is provided with a hook E rigidly secured to it, and which engages a pin F provided with an anti-friction roller F mounted in thering B. Between the sleeve D and the bell-shaped sleeve C is a controlling spring G in compression. The sleeve D carries a rack D, and is cut away as shown at 2o in which it is'tilted, or tends to be tilted,

2 in order to balance the centrifugal actionof the hook E which is mounted on that side of the sleeve. The spindle is, driven by apinion H, and the rack D engages a pinion J connected to the speed indicator pointer in any well-known way.

The ope'ation of the device is 'as follows :When the spindle is revolved centrifugal forces tend to make the ring B assume a horizontal positiom such as is indicated in chain line in Fig. 1. As the ring moves from-the position of rest shown in full line, it carries with it the hook E, so displacing the sleeve D against the controlling force of the spring G, finally tak ing up some position intermediate between the position of rest and that shown in chain line. The condition of the sleeve D under the action of the force applied to the hook E and that exerted by the spring G, is one owing to the want of lateral. symmetry arising from the fact that only one hook is employed. The result of this is that frictional binding between the sleeve and the spindle tends to be produced, and would be unchecked if the camface E of the hook were at right angles to the spindle, and would be enhanced if the face E were upwardly sloped. By giving to the face E, however, a slight downward (as viewed in Fig. 1) slope, a force is introduced, by the action thereon of the pin F, which counteracts more or less completely the said tilting action, so reducing or eliminating'the consequent binding effect. The reduction or removal of the binding effect hasfor its result a reater responsiveness in the indications of the instrument, that is to say, there is a less changeof speed necessary to produce some movement of the sleeve D, since the latter is no longer held by the same frictional binding force, and does not therefore require the same force to be exerted before it will move. The cam-face of the hook may further be shaped, apart from being inclined to the spindle, in any way that may 7 be necessary to produce a desired arrangement ofthe scale. For example, it may be convenient to have the very early indications of an instrument intended for use on a motor-car up to, say, twelve miles an hour, somewhat crowded on the scale, while those from twelve to thirty-five may be more openly spaced, and those above thirtyfive be again somewhat closely spaced; any desired arrangement of spacing may be ob- Copies of this patent may be obtained for five cents each, by addressing 7 Washington, 70;

tained by suitably shaping the cam-face of the hook.

It is preferred to arrange thatthe weight ed arm-or arms, or,,in the construction illustrated, the plane of thering B,; sh'all be somewhat inclined t-U 'the'a-Xis of the spindie, and that the upward 'movement shall be limited to that inwhich the inclination reaches, say, 45, as 'a maximum, in order that the hereinbefore referred to irregularity of scale may be reduced to some ex;

tent, apartfrom the reduction effected by specially shaping the caln-ffaceQ to secure by Letters Patent is':-

1. In a centrifugal governor, the combination ofla rotatable shaft raring surrounding and pivo-tallyimounted' on-the shaft; a sleeve slidably mounted on the shaft; a hook carried by lft-lre sleeve and engaging with hat'I claim as my inventlon and-desire c said ring and adapted to be moved thereby;

and a sprlng mounted on the shaft engaging with and holding said sleeve under tension, substantially as described.

2. In a centrifugal governor, the combinationof a rotatable shaft a ring surrounding and pivotally mounted on the shaft; a roller journaled on said ring; a sleeve slidably mounted on the shaft; a hook carried by said sleeve and'having an inclined portion engaging with said roller, said ring adapted to move the sleeve through said roller and hook engagement; and a spring mounted on the shaft engagingwith and holding said sleeve under tension, substantially as described.

3. In a centrifugcl governor, the combination of a rotatable shaft; aslee've fixedly mounted on said shaft; a ring surrounding and pivotally mounted on said sleeve; a sleeve slidably mounted on the'shaft; a hook carried by said sleeve and havingan inclinec portion engaging with said ring, said ring adapted to move the slidable sleeve through said hook engagement; and a s ringmounted on theshaft and hav ngjlt's respective 'endsengagingwith said fixed and movable sleeves and adapted to hold the latter under tension, substantially as described.

In testimony whereof I-have signedmy 7 name to this specification in the presence of two subscribingwitnesses.

reruns orro onna.

Witnesses: i H. D. Jamison, Y O. P. Trnnon the Commissioner-def Patents. 

